Related topics: climate change , greenhouse gas , global warming , fossil fuels , carbon dioxide emissions
Carbon dioxide
hideCarbon dioxide (chemical formula: CO2) is a chemical compound composed of two oxygen atoms covalently bonded to a single carbon atom. It is a gas at standard temperature and pressure and exists in Earth's atmosphere in this state.
Carbon dioxide is used by plants during photosynthesis to make sugars, which may either be consumed in respiration or used as the raw material to produce other organic compounds needed for plant growth and development. It is produced during respiration by plants, and by all animals, fungi and microorganisms that depend either directly or indirectly on plants for food. It is thus a major component of the carbon cycle. Carbon dioxide is generated as a by-product of the combustion of fossil fuels or the burning of vegetable matter, among other chemical processes. Large amounts of carbon dioxide are emitted from volcanoes and other geothermal processes such as hot springs and geysers and by the dissolution of carbonates in crustal rocks.
As of March 2009[update], carbon dioxide in the Earth's atmosphere is at a concentration of 387 ppm by volume. Atmospheric concentrations of carbon dioxide fluctuate slightly with the change of the seasons, driven primarily by seasonal plant growth in the Northern Hemisphere. Concentrations of carbon dioxide fall during the northern spring and summer as plants consume the gas, and rise during the northern autumn and winter as plants go dormant, die and decay. Carbon dioxide is a greenhouse gas as it transmits visible light but absorbs strongly in the infrared and near-infrared.
Carbon dioxide has no liquid state at pressures below 5.1 atmospheres. At 1 atmosphere (near mean sea level pressure), the gas deposits directly to a solid at temperatures below −78 °C and the solid sublimes directly to a gas above −78 °C. In its solid state, carbon dioxide is commonly called dry ice.
CO2 is an acidic oxide: an aqueous solution turns litmus from blue to pink. It is the anhydride of carbonic acid, an acid which is unstable and is known to exist only in aqueous solution.
CO2 is toxic in higher concentrations: 1% (10,000 ppm) will make some people feel drowsy. Concentrations of 7% to 10% cause dizziness, headache, visual and hearing dysfunction, and unconsciousness within a few minutes to an hour.
For more information about Carbon dioxide, read the full article at
Wikipedia.
This text uses material from Wikipedia and is available under the GNU Free Documentation License.
News tagged with carbon dioxide
Potatoes, algae replace oil in US company's plastics
Dec 21, 2009 |
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Frederic Scheer is biding his time, convinced that by 2013 the price of oil will be so high that his bio-plastics, made from vegetables and plants, will be highly marketable.
Global warming likely to be amplified by slow changes to Earth systems
Space & Earth / Earth Sciences
Dec 20, 2009 |
2.8 / 5 (46) |
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Researchers studying a period of high carbon dioxide levels and warm climate several million years ago have concluded that slow changes such as melting ice sheets amplified the initial warming caused by greenhouse ...
Climate talks end with eye on next year
Dec 19, 2009 |
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(AP) -- A historic U.N. climate conference ended Saturday with only a nonbinding "Copenhagen Accord" to show for two weeks of debate and frustration. It was a deal short on concrete steps against global warming, ...
Replicating Climate Change to Forecast its Effects
Dec 17, 2009 |
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(PhysOrg.com) -- Agricultural Research Service (ARS) scientists are replicating the effects of climate change to see what the future holds for soybeans, wheat and the soils where they grow.
Soil Microorganisms? Role Cited as a Missing Factor in Climate Change Equation
Dec 17, 2009 |
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(PhysOrg.com) -- Those seeking to understand and predict climate change can now use an additional tool to calculate carbon dioxide exchanges on land, according to a scientific journal article co-authored by a University of ...
NASA, Google offer more precise emissions tracking
Dec 17, 2009 |
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(AP) -- The question is a potential deal-killer: If nations ever agree to slash greenhouse gas emissions, how will the world know if they live up to their pledges?
NASA Calculates a Carbon Budget for California
Dec 16, 2009 |
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(PhysOrg.com) -- While world organizations struggle to find a benchmark and tracking standards for greenhouse gas (GHG) emissions, NASA has been supporting California’s new carbon emissions inventory report, using its satellite ...
NASA Outlines Recent Breakthroughs in Greenhouse Gas Research (w/ Video)
Space & Earth / Earth Sciences
Dec 15, 2009 |
3.7 / 5 (6) |
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(PhysOrg.com) -- Researchers studying carbon dioxide, a leading greenhouse gas and a key driver of global climate change, now have a new tool at their disposal: daily global measurements of carbon dioxide ...
New results from a terra-ific decade in orbit
Space & Earth / Earth Sciences
Dec 15, 2009 |
5 / 5 (1) |
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December 18, 2009, marks the tenth year since the launch of Terra, one of NASA's "flagship" Earth observing satellites. But the decade is more than just a mechanical milestone. With each additional day and ...
Home heating efficiencies offer 'hat trick' of savings: study
Dec 15, 2009 |
3 / 5 (1) |
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Improving the energy efficiency of Maryland homes heated by natural gas would generate a "hat trick" of economic and environmental benefits over the next 10 years, including more than 80,000 new jobs, savings of hundreds ...
Going underground for a climate solution
Space & Earth / Earth Sciences
Dec 14, 2009 |
2 / 5 (4) |
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(PhysOrg.com) -- Hoping to help fix the Earth's atmosphere, Catherine Peters recently found herself 4,100 feet underground.
Gas improves blood flow and organ status during minimally invasive surgery
Dec 14, 2009 |
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As good as laparoscopy is in preventing some of the stresses of open surgery on the body, it does have drawbacks, including reduced blood flow and organ dysfunction. Laparoscopy is a type of surgery in the abdomen done through ...
World's mayors tackle climate change on their own
Dec 14, 2009 |
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(AP) -- It isn't easy getting Italy's city dwellers out of their Fiats, off their Vespa scooters and onto bicycles to ride to work, "like here in Copenhagen," says an Italian environmental official.
Climate projections underestimate CO2 impact
Space & Earth / Earth Sciences
Dec 10, 2009 |
2.8 / 5 (16) |
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The climate may be 30-50 percent more sensitive to atmospheric carbon dioxide in the long term than previously thought, according to a recent study published in Nature Geoscience.
Researchers engineer bacteria to turn carbon dioxide into liquid fuel
Dec 10, 2009 |
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(PhysOrg.com) -- The genetically modified cyanobacterium consumes carbon dioxide and produces the liquid fuel isobutanol by using energy from sunlight.
